孔隙率和孔径对陶粒吸声材料吸声性能的影响(英文)

Effects of Porosity and Pore Size on Sound Absorption Characteristic of Ceramsite Porous Material

用流阻法和显微分析法定量表征材料的孔隙状况,研究以陶粒为主要骨料的多孔吸声材料在不同有效孔隙率和中值孔径下的吸声性能。结果表明陶粒吸声材料的NRC随着流阻的增加先增后减,当流阻为1 144.07 Pa.s/m3,材料吸声性能达到最佳;材料的中值孔径在0.71～1.44 mm这一范围,当其减少时,吸声性能降低;随着有效孔隙率的增加,NRC呈线性上升的趋势,其中高频吸声性能对材料内部孔隙状况的变化更敏感。

The methods of air-flow resistivity and microscopic analysis were used to quantitatively characterize the porosity of the porous materials and investigate the sound absorption of the porous sound-absorbing materials like ceramsite as an aggregate at different porosities or median pore diameters.The results show that the noise reduction coefficient（αNRC） of the ceramsite sound-absorbing material increases at the beginning and then decreases with increasing the air-flow resistivity at the sound absorption of 1 144.07 Pas/m^3.The sound absorp-tion decreased with decreasing the median pore diameter in the size range of 0.71–1.44 mm.The αNRC could increase with the increase of the effective porosity.The high-frequency sound absorption was more sensitive to the changes of the internal porosity of the material.